(1) An interested person may attend a deposition and may intervene in any proceeding the department initiates to enforce the summons and such person is bound by the decision in such proceeding whether or not the person intervenes.
(2) Any person entitled to notice of a summons may begin a proceeding to intervene in either the district court in the county in which the person resides or in the district court of the First Judicial District not later than 20 days after the notice of administrative summons is received. Notice is deemed given as provided for in Rule 45, Montana Rules of Civil Procedure.
(3) If a person intervenes, the person shall mail, by registered or certified mail, a copy of the petition to the person summoned and to the department's contact person. In any proceeding to intervene, the department may seek to compel compliance with the summons.